Anonymous gifts are common. But a climate group says a $10 million gift it got is an all-out mystery

A climate philanthropy organization, Giving Green, received a $10 million anonymous donation in April and thinks that the same donor may have given even more. Giving Green researches and recommends donating to a handful of nonprofits they think have the potential to make a significant difference in preventing climate change. Founder Dan Stein says the same donor may actually have given as much as $17 million more directly to those organizations in the last two years. Tory Martin is a director at the Dorothy A. Johnson Center for Philanthropy. She says while it’s not unusual for nonprofits to receive anonymous gifts, usually, those gifts grow out of long-term relationships with donors.